 Crohn's disease
is an inflammatory condition of the digestive tract that affects children
and adults. The cause of Crohn's disease is unknown, but heredity factors
are suspected to contribute. Common symptoms of Crohn's disease include
mouth sores, diarrhea, abdominal pain, weight loss, and fever. Patients can
also have symptoms outside of the digestive tract, including a skin rash,
joint pain, eye redness, and, less commonly, liver problems. This disease is
typically diagnosed by the presence of specific symptoms and by tests, such
as colonoscopy and imaging tests that use barium.

Although Crohn's disease is usually chronic, medical and surgical
treatment can help control the course of the disease and many patients
experience long periods of symptom-free remission. Most patients with
Crohn's disease have a normal life even though they have to contend with an
ongoing problem. Intense research is helping to uncover the cause of the
disease and continues to lead to the development of new treatments.

Treatment is individualized and depends upon the area of the digestive
tract affected, the type of symptoms, and the activity of the disease. You
should take a role in your medical decisions and care by learning as much as
you can about the condition, following treatment guidelines, and promptly
alerting your doctor to any changes in your condition.

WHAT CAUSES CROHN'S DISEASE?  The exact cause of Crohn's disease
is unknown. What is known is that the disease tends to run in families and
affects certain populations more than others, suggesting that genetic
factors are important. Although research has been done to identify
environmental factors and infections that might cause the disease, no cause
has been consistently found.

The current belief is that some kind of trigger in a genetically
susceptible person leads the body's immune system to inappropriately cause
inflammation in the digestive tract. Bacteria and food substances in the
digestive tract probably also have a role. Once the inflammation begins, it
causes damage to the intestines; this damage is mainly responsible for the
symptoms of the disease.

WHAT IS THE TYPICAL PATTERN OF CROHN'S DISEASE?  Crohn's disease
usually follows a pattern of exacerbations and remissions. About 10 to 20
percent of patients will enter remission after their first exacerbation of
Crohn's disease. The pattern in other patients can be quite variable,
ranging from recurrent periods (weeks to months) of symptoms (such as mild
diarrhea and cramping) to, less commonly, severe and disabling symptoms
(such as severe abdominal pain and bowel obstruction). Treatment can help
drive active disease into remission and then prolong remission.

Most cases of Crohn's disease primarily affect the terminal ileum (a
region of the small intestine) and the colon, producing ileitis
(inflammation of the ileum) and colitis (inflammation of the colon),
respectively (show figure). Inflammation in these areas can lead to the
formation of abnormal passages (fistulas), perforation of the intestinal
wall, or narrowing of the digestive tract (stricture) and obstruction.
Crohn's disease can also affect the perianal area, producing fissures,
ulcers, pockets of pus (abscesses), and fistulas.

WHAT DRUGS ARE USED TO TREAT CROHN'S DISEASE?  Many different
drugs are used to treat Crohn's disease. Your doctor's choice of medications
will depend upon the area of the digestive tract affected by the disease and
your symptoms. Some of the typical approaches are described below. The
following is a summary of some of the drugs that are commonly used.

Sulfasalazine  Sulfasalazine was one of the first drugs used to
treat Crohn's disease and is still used for treating Crohn's disease
restricted to the colon. Sulfasalazine usually begins to reduce symptoms
within a few days, but its full effect may require up to four weeks of
treatment. A problem with sulfasalazine is that it can cause allergic
reactions in a minority of patients and can cause headaches, particularly
when given in high doses.

5-Aminosalicylates  The 5-aminosalicylate (5-ASA) drugs (such as
Asacol and Pentasa) are similar to sulfasalazine but are less likely to
cause headaches and allergic reactions. An advantage is that they can be
given in relatively high doses compared to sulfasalazine. In addition, they
are formulated to be released in the terminal ileum (in the case of Asacol)
and throughout the small intestine (in the case of Pentasa), which permits
the drugs to be targeted to inflamed areas. Their major disadvantage is
their relatively high cost. These drugs are helpful in achieving and
maintaining remission. They usually begin to reduce symptoms within a few
days, but their full effect may require up to four weeks of treatment.

Antibiotics  Antibiotics can reduce the bacterial contribution to
the inflammation of Crohn's disease. The antibiotics most frequently used
are metronidazole and ciprofloxacin. Metronidazole is most helpful in
patients with Crohn's disease involving the colon and perianal region. A
problem with it, however, is that it causes an unpleasant metallic taste,
which goes away once the drug is discontinued, and can cause peripheral
neuropathy (damage to the nerves responsible for sensation in the hands and
feet) with long-term use. Peripheral neuropathy can be permanent. Alcohol
should be avoided in patients taking metronidazole because when taken
together metronidazole plus alcohol can lead to nausea, headaches, and
flushing.

Steroids  Steroids (such as prednisone and budesonide) can help
drive active, moderate to severe Crohn's disease into remission, but they do
not prolong remission and they have many serious side effects when taken for
long periods of time.

Immunomodulator drugs  Immunomodulator drugs decrease the
inflammation associated with Crohn's disease. The most commonly used drugs
include azathioprine, 6-mercaptopurine, and methotrexate, although many new
drugs continue to be studied and are already used occasionally. These drugs
have traditionally been used for patients who have not responded to
"first line" therapy with drugs such as antibiotics, sulfasalazine,
and 5-aminosalicylates, particularly those who depend upon steroids to
control symptoms. These drugs are also very helpful for maintaining
remission.

Immunomodulator drugs take a long time (three to six months) to produce a
maximal effect and are often prescribed for long-term therapy. The major
side effects of these drugs include lowering of the white blood cell count
(the cells that help fight off infection in the body), hepatitis
(inflammation of the liver), and pancreatitis (inflammation of the
pancreas). As a result, your doctor will have to check blood tests
regularly.

Another drug that is used occasionally is cyclosporine, which is a strong
suppressor of the immune system. Its principal role in Crohn's disease is
for patients with active fistulizing disease who have not responded to other
types of therapy.

Infliximab  Infliximab is an antibody that neutralizes an
inflammatory substance in your body that is called tumor necrosis factor. It
is a relatively new agent and is generally reserved for patients who do not
respond well to "first line" therapy with antibiotics and 5-ASA
drugs. It is especially effective in patients with fistulizing Crohn's
disease. In one study, for example, closure of all fistulas was observed in
55 and 38 percent of patients receiving the 5 and 10 mg/kg dose of
Infliximab, respectively, compared to 13 percent of those receiving placebo
(a sugar pill).

The main side effects of infliximab are allergic reactions and
infections. Another concern is that a small number of patients who have
received Infliximab have developed lymphoma (a cancer of the lymphatic
system). While this number is much smaller than the large number of patients
who have benefited from Infliximab, it is still not a drug considered to be
a "first line" agent. Furthermore, the effects of the drug only
last for a few weeks (8 to 10 on average) in most people; thus repeated
dosing is usually needed. It is also very expensive (approximately $2500 per
dose).

WHAT SHOULD I EAT?  Most patients with Crohn's disease can
identify foods that tend to exacerbate their symptoms, although the specific
foods implicated vary among patients. Many patients with Crohn's disease
tend to avoid eating, since eating can worsen diarrhea and cramps. This has
potentially serious consequences since it can lead to malnutrition. Thus, it
is important that you carefully discuss your dietary concerns with your
doctor, who may also arrange for you to have a consultation with a
dietitian.

IS THERE ANYTHING ELSE I SHOULD DO?  As discussed above, one of
the most important things for you to do is to avoid becoming malnourished.
In addition, you should exercise regularly to maintain your general health.
Smoking worsens Crohn's disease and should be avoided. You should also avoid
taking nonsteroidal antiinflammatory drugs (such as ibuprofen and naprosyn),
since they can worsen the disease.

CAN I HAVE CHILDREN? Men and women with Crohn's disease can have
children. However, several issues, such as the safety of the various drugs
used for your treatment, may arise that warrant discussion with your doctor.
Thus, you should tell your doctor if you are contemplating pregnancy.

Children of parents with Crohn's disease have been reported to be 3 to 20
times more likely to develop Crohn's disease than the general population.
However, there is currently no way to predict the risk in an individual
child.

SUPPORT  Do not underestimate the value of sharing your concerns
with other people with Crohn's disease. Ask your doctor about support
groups. The Crohn's and Colitis Foundation of America also has information
about support groups. They can be reached on the Internet at http://www.ccfa.org/.

WHAT IS THE MEDICAL TREATMENT FOR CROHN'S DISEASE?  In most cases,
drugs, nutritional support, and watchful waiting are the first line of
treatment for Crohn's disease, although some patients may require surgery.
The specific approach depends upon the areas of the digestive tract that are
affected and the activity of disease.

Mouth sores  The often painful mouth sores of Crohn's disease
usually respond to treatment of intestinal disease. Topical drugs (such as
hydrocortisone or sucralfate) may help heal these sores.

Inflammation of the stomach and upper small intestine  Crohn's
disease of the upper part of the digestive tract may respond to drugs used
to treat stomach and intestinal ulcers. In severe cases, steroids and
immunomodulator drugs may be necessary to control inflammation.

Ileitis  Active ileitis is first treated with 5-aminosalicylate
drugs; antibiotics, steroids, and immunomodulator drugs may be required in
patients with moderate to severe symptoms. Antidiarrheal drugs can also help
relieve diarrhea. Severe ileitis may require close monitoring, bowel rest
(avoiding solid food), enteral feeding (feeding by a nasogastric tube) or
total parenteral feeding (intravenous feeding), and surgery. The remission
of ileitis can be maintained with 5-aminosalicylate drugs in some patients.

Ileocolitis and colitis  Active Crohn's disease that affects the
ileum and colon or the colon alone is first treated with sulfasalazine or a
5-ASA drug. In some patients, treatment will also include antibiotics and
steroids. Severe ileocolitis or colitis may require hospitalization, bowel
rest, enteral feeding or parenteral feeding, and long-term treatment with
immunomodulator drugs. The 5-ASA drugs are usually used to maintain
remission of ileocolitis and colitis.

Perianal complications  About 35 to 45 percent of patients with
Crohn's disease will develop perianal complications at some time during
their disease. If abscesses, fissures, or fistulas do not produce symptoms,
they may not require treatment. Some will spontaneously heal, but others
will require treatment with antibiotics, steroid suppositories,
immunomodulator drugs, or surgery. Sitz baths and careful, gentle cleaning
of the perianal area can also promote healing. Although treatment resolves
most perianal complications, recurrence is frustratingly common and may
require long-term treatment.

Chronic disease of the perianal area can also lead to narrowing of the
anal canal. This narrowing can be partially reversed by gentle therapeutic
dilation, which is often started in the hospital and continued at home.

WHAT SECONDARY PROBLEMS ARE ASSOCIATED WITH CROHN'S DISEASE?  Over
time, the intestinal problems of Crohn's disease and the ongoing
inflammation can lead to secondary health problems. Fortunately, many of
these problems can be anticipated and prevented; if they do occur, most can
be successfully treated.

Malnutrition  Between 50 and 70 percent of patients with Crohn's
disease develop malnutrition or are underweight. There may be many
consequences of malnutrition, including delayed growth and puberty in
children, osteoporosis, a decreased ability to withstand surgery, and
psychosocial problems.

Malnutrition can often be prevented by regular nutritional assessments.
Typically, a doctor or dietitian reviews a patient's diet, checks a
patient's body composition, and orders laboratory tests to detect
deficiencies. In most patients, caloric and nutrient supplementation can
reverse the malnutrition associated with Crohn's disease. Although patients
with Crohn's disease often have a poor appetite, they should not restrict
their dietary intake unless they are instructed to do so by their doctor.

Enteral feeding (feeding by a nasogastric tube) with special, elemental,
or polymeric diets and total parenteral feeding (intravenous feeding) can
provide nutrients when the digestive tract cannot tolerate normal food or
has been effectively shortened by disease or surgery. In some cases,
parenteral feeding can also help achieve remission. However, for the
majority of patients with Crohn's disease, neither feeding procedure is a
practical option for long-term nutrition.

Bone complications  Up to 30 percent of patients with Crohn's
disease develop osteoporosis, which can lead to bone fractures. Patients who
take steroids for long periods of time and postmenopausal women are
particularly at risk. Regular bone mineral density tests can detect early
osteoporosis in patients with Crohn's disease.

Osteoporosis usually results from deficiencies of vitamin D, calcium, and
sex hormones (estrogen and testosterone). Regular blood tests will detect
deficiencies, and supplements and drugs can be used to restore the levels to
normal. Patients can further strengthen their bones by performing
low-impact, weight-bearing exercises at least twice a week.

Liver and gallbladder complications  Crohn's disease can lead to
inflammation of the liver, which often responds to the drugs also used to
treat intestinal Crohn's disease. Crohn's disease can rarely cause
inflammation of the bile ducts (a disease called primary sclerosing
cholangitis). Crohn's disease can also increase the likelihood of
gallstones, which may not require treatment or may require surgical removal.

Colorectal cancer  Overall, patients with Crohn's disease have an
increased risk of developing colorectal cancer in areas of active
inflammation. However, cancer usually does not arise until a patient has had
Crohn's disease for many years. Some doctors recommend a regular screening
colonoscopy to identify premalignant and malignant changes in the colon.

CAN CROHN'S DISEASE AFFECT OTHER AREAS OF THE BODY?  Crohn's
disease can lead to inflammation of other tissues, commonly called "extraintestinal"
disease. Possible symptoms include reddening and swelling of the skin, eye
pain and irritation or vision problems, and coughing, wheezing, or
difficulty breathing.

Skin inflammation  Crohn's disease can lead to skin inflammation
in up to 15 percent of patients. This inflammation often subsides when the
intestinal symptoms are treated, but steroids may be required.

Eye inflammation  Inflammation of the eyes occurs in up to 5
percent of patients with Crohn's disease. This inflammation often responds
to the drugs used to treat Crohn's disease, but careful monitoring is
necessary to prevent complications such as glaucoma.

Lung and airway inflammation  Rarely, Crohn's disease may lead to
inflammation of the airways and lungs. This inflammation may be treated with
nonsteroidal anti-inflammatory drugs, inhaled steroids, or oral steroids.

WHEN IS SURGERY NECESSARY?  Medical treatment can help control the
symptoms and complications of Crohn's disease and may delay the need for
surgery. Surgery is usually used as a last resort since it does not cure the
disease, although in some patients it may be the fastest way to restore
health. About 80 percent of patients with Crohn's disease will require an
operation at some time, usually for serious problems. Surgery is used to
stop bleeding, to close fistulas and bypass obstructions, and often simply
to remove the affected areas of the intestine.

WHAT CAN I EXPECT AFTER SURGERY?  It is important to have
realistic expectations of surgery. Surgery can improve a patient's medical
condition and can even be lifesaving. However, surgery does not cure Crohn's
disease, and recurrence is likely.

Between 85 and 90 percent of patients are symptom-free during the year
following surgery, and up to 20 percent of patients are still symptom-free
15 years after surgery. If Crohn's disease is confined to the colon and the
colon is removed, only 10 percent of patients will have a recurrence within
10 years. Prompt and long-term drug treatment started at the time of surgery
decreases the risk of recurrence in many patients with Crohn's disease.

If the surgery creates an ileostomy or colostomy (an opening for
collecting intestinal contents), a stomal therapist can answer questions
about the procedure. Patients with ostomies usually lead a normal life.

HOW IS CROHN'S DISEASE TREATED IF IT RECURS AFTER REMISSION OR SURGERY?
 Recurrent Crohn's disease is usually treated according to the same
guidelines used to treat the initial episode of Crohn's disease. In some
cases, stronger drugs are used to treat a recurrence.

WHAT ARE SPECIAL CONCERNS WHEN CROHN'S DISEASE OCCURS IN CHILDREN AND
ADOLESCENTS?  Crohn's disease appears before the age of 18 in about
20 percent of patients. If the disease is not treated, about one-half of
these children will have short stature or delayed growth. Aggressive
nutritional therapy can help normalize growth. This therapy may include
supplements, a high-calorie diet, and sometimes enteral feeding.

Because steroids can also retard growth and lead to osteoporosis in
children, these agents are often the last used if a child's Crohn's disease
requires long-term therapy. Height, weight, and bone mineral density must be
closely monitored in children who take steroids.

Children with Crohn's disease may experience significant psychosocial
problems because their condition interferes with day-to-day functioning and
affects their interaction with peers. If your child seems withdrawn or is
experiencing school or social difficulties, be sure to bring these matters
to your doctor's attention.

WHAT TREATMENTS ARE ON THE HORIZON?  Several investigational
therapies show promise for the treatment of Crohn's disease. The majority of
the new drugs that are being developed help quiet inflammation. Many of
these drugs are currently undergoing clinical trials. As of yet, none have
been proven to be better than currently available treatments. You should
tell your doctor if you are interested in participating in a clinical trial.
You can also contact your nearest academic medical center (a medical center
affiliated with a medical school) and ask for the gastroenterology
department to see if they are conducting clinical research in Crohn's
disease.